Method of joining pipes and apparatus for facilitating the same

ABSTRACT

An apparatus and method for joining pipes includes a plate for melting mating surfaces of the pipes to be joined. Additionally, the apparatus utilizes a vacuum in order to push the first and second pipes together in lieu of hand or mechanical pressure which may be inconsistent. Additionally, the vacuum allows the pipes to be joined to settle on each other in order to create a pressure about a periphery of the end of the pipe being joined to the other pipe. The consistent pressure creates a very strong joint between the first and second pipes.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

Not Applicable

BACKGROUND

The various aspects and embodiments described herein relate to anapparatus and method for joining first and second pipes.

Plastic piping is installed underground and/or above ground to transportliquid, air, gas, waste, etc. to or from home or business. These pipeshave a need for many connection branches which may need to be installedin a variation of sizes and angles. Whether the branch is tapping ontoan existing line or a newly installed pipe, there is a common need to beable to install these connections within a confined space (excavation,vault, etc). In addition there is a need for a process to be able toinstall branch connections at variable angles to influence theperformance of the piping system or to limit the complexity of theconnection.

Accordingly, there is a need in the art for a method and apparatus tofacilitate joining first and second pipes.

BRIEF SUMMARY

A method for joining pipes and an apparatus for facilitating the sameare disclosed herein. The apparatus may include a plate for meltingmating surfaces of first and second pipes, or in other words, raisingits temperature above its softening temperature. The apparatus may alsoinclude a cap with a vacuum for generating a negative pressure withinthe first and/or second pipes to push the first and second pipestogether and also to hold the first and second pipes against the plate.The mating surfaces on the first and second pipes are initially melted.Once the mating surfaces have reached its softening temperature, theplate is removed from between the first and second pipes. The matingsurfaces are connected to each other (i.e., placed in contact with eachother). The cap is placed over one of the first and second pipes and thevacuum activated in order to create a negative pressure within the pipe.The negative pressure pushes the first and second pipes towards eachother. The operator allows the first and second pipes to settle uponeach other. This means that the angle between the first and second pipesmay be slightly different from the intended angle in order that thepressure between the first and second pipes can be equalized about aperiphery of the distal end of the first pipe. This creates anespecially strong joint.

Additionally, by using a vacuum to create the negative pressure andforce the first and second pipes together, the user need not apply handpressure which could be inconsistent as well as awkward when the firstand second pipes are skewed to each other or when the first and secondpipes are joined to each other end to end at a skewed angle.

More particularly, in an aspect, a method of forming a liquid tight sealbetween a distal end of a first pipe and a second pipe is disclosed. Themethod may comprise the steps of heating the distal end of the firstpipe and the second pipe with a heater until the distal end(s) of thefirst pipe and the second pipe have reached a softening temperature;contacting the distal end of the first pipe to the second pipe; creatinga negative pressure within a cavity of the first pipe after thecontacting step so that the distal end of the first pipe is pushed intothe second pipe; and applying even pressure about the circumference ofthe distal end of the first pipe onto the second pipe.

The heating step may be performed until at least ⅛ inch and morepreferably ½ inch (depending on the size and type of material) of thedistal end of the first pipe has reached the softening temperature of amaterial of the pipe.

The heating step may be performed with a plate having opposed first andsecond sides sized and configured to mate with the distal end of thefirst pipe and the exterior surface or distal end of the second pipe.The first side may have a convex configuration. The second side may havea concave configuration. Alternatively, the first and second sides maybe flat.

The method may further comprise the step of forming a vacuum with anedge of a cup to the exterior surface of the second pipe.

The forming the vacuum step may include the step of capping an opposeddistal end of the first pipe with a cap which is in fluid communicationwith a vacuum device for creating negative pressure.

The applying step may include the step of allowing an angularrelationship between the first pipe and the second pipe to change asnegative pressure is applied to the cavity of the first pipe, and thedistal end of the first pipe is pushed into the second pipe.

The method may further comprise the step of creating the negativepressure within the cavity of the first pipe during the heating step sothat the negative pressure created in the cavity of the first pipe issufficient to hold the first side of the plate of the heater onto thedistal end of the first pipe.

The plate of the heater may have a through hole so that the negativepressure created in the cavity of the first pipe is applied between theplate and the second pipe to hold the plate onto the second pipe. Thethrough hole may also have a fitting that can be connected to a hose orline that provides negative pressure to the space between the plate andthe second pipe to hold the plate onto the second pipe initially whileraising the temperature of the second pipe to its softening temperature.This may be accomplished without the first pipe attached to theheater/plate. After a certain depth of material of the second pipe hasbeen raised to an elevated temperature below its softening temperature,the vacuum line is removed from the fitting and the first pipe is placedon the heater/plate. Vacuum is established in the cavity of the firstpipe and the vacuum is communicated to the space between the plate andthe second pipe through the through hole or fitting so that the heatercan continue to raise a depth of the surfaces of the first and secondpipes to its softening temperature.

In the method, the distal end of the first pipe may be attached to anexterior surface of the second pipe. The distal end of the first pipemay be attached to a distal end of the second pipe. Also, the vacuum maybe created by capping an opposed distal end of the second pipe.

In another aspect, a pipe attaching machine for forming a liquid tightseal between a distal end of a first pipe and a second pipe isdisclosed. The pipe attaching machine may comprise a heater, a cap and avacuum. The heater may have a plate and a handle. The plate may haveopposed first and second sides sized and configured to mate with thedistal end of the first pipe and the second pipe. The plate may beoperative to provide heat to the distal end of the first pipe and thesecond pipe for raising its temperature to a softening temperature ofthe first and second pipes. The handle may be attached to the plate. Thehandle may be insulated from the plate so that the handle can be grippedby a person to manipulate the heater plate even when the plate isheated. The cap may be sized and configured to provide a seal with anopposed distal end of the first pipe. The vacuum may be operative tocreate a negative pressure. The vacuum may be in fluid communicationwith the cap to create negative pressure within a cavity of the firstpipe when the cap is mounted to the opposed distal end of the first pipeto hold the first pipe to the heater when heating (i.e., melting) thedistal end of the first pipe and also to hold the distal end against theexterior surface of the second pipe when attaching the distal end of thefirst pipe to the second pipe.

The plate may have a through hole so that negative pressure created inthe cavity of the first pipe may be applied between the plate and thesecond pipe to hold the plate to the second pipe.

The first side of the plate may have a convex configuration sized and beconfigured to mate with the distal end of the first pipe. The secondside of the plate may have a concave configuration sized and configuredto mate with an exterior surface of the second pipe.

The plate may also have a cup disposed in the second side. An edge ofthe cup may be sized and configured to contact the exterior surface ofthe second pipe before the concave configured second side of the plateto more quickly form a seal to create a negative pressure between thesecond side of the plate and the exterior surface of the second pipe.Alternatively, in lieu of the cup disposed on the second side of theplate, the seal may be established by contact with a gasket or softeningplastic cup or ring.

In an alternate embodiment, the first side of the plate may be flat andbe sized and configured to mate with the distal end of the first pipe.Also, the second side of the plate may be flat and be sized andconfigured to mate with a distal end of the second pipe.

In another aspect, a method for expediting fusion of a distal end of afirst pipe to a contact surface of a second pipe is disclosed. Themethod may comprise the steps of cooling a distal end portion of thefirst pipe and/or a contact patch portion of the second pipe below itsnormal temperature; heating the distal end of the first pipe and/or thecontact surface of the second pipe so that a portion less than thedistal end portion and/or less than the contact patch portion of thesecond pipe is heated to a softening temperature of a material of thefirst pipe and/or second pipe; pushing the distal end of the first pipeonto the contact surface of the second pipe; and directing heat awayfrom the distal end of the first pipe and/or the contact patch of thesecond pipe since less than the distal end portion of the first pipeand/or less than the contact patch portion of the second pipe was heatedand the entire distal end portion of the first pipe and the entirecontact patch portion was cooled below its normal temperature.

The contact patch may be a distal end of the second pipe. The contactpatch may be an exterior surface of the second pipe.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features and advantages of the various embodimentsdisclosed herein will be better understood with respect to the followingdescription and drawings, in which like numbers refer to like partsthroughout, and in which:

FIG. 1 is a top view of a ditch showing joined first and second pipes;

FIG. 2 is a flowchart of a method for joining first and second pipes;

FIG. 3 is a perspective view of an apparatus used to melt matingsurfaces of first and second pipes for joining;

FIG. 4 is a perspective view of the apparatus being removed from betweenthe first and second pipes;

FIG. 5 is an enlarged view of a joint between the first and secondpipes;

FIG. 6 illustrates the mating surfaces of the first and second pipesforming a bead about a periphery of the joint;

FIG. 7 is a perspective view of a first side of a plate for melting thesurfaces of the first and second pipes;

FIG. 8 is a perspective view of a second side of the plate shown in FIG.7;

FIG. 9 is an alternate embodiment of the plate for facilitating aquicker way to establish a vacuum;

FIG. 9A is a cross sectional view of the alternate embodiment;

FIG. 10 illustrates a core bit drilling a hole through a surface of apipe to establish fluid communication between the first and secondpipes;

FIG. 11 illustrates the apparatus for joining first and second pipes endto end; and

FIG. 12 illustrates a cooling unit for expediting the time for joiningfirst and second pipes.

DETAILED DESCRIPTION

Referring now to the drawings, a method and apparatus is disclosed forjoining a branch pipe 10 to a main pipe 12 at a skewed angle 14 so thatgas, fluid and other solid materials can flow through the branch pipe 10in the direction of arrow 16 to flow with gas, fluid and other solidmaterial through the main pipe 12 in the direction of arrow 18.

A connection between a distal end 22 of the branch pipe 10 and anexterior surface 24 of the main pipe 12 is referred to as a joint 20.The distal end 22 of the branch pipe 10 and the mating portion of theexterior surface 24 of the main pipe 12 are heated to a softeningtemperature then pushed together to form a chemical bond and join thebranch pipe 10 to the main pipe 12. The periphery of the distal end 22when pushed into the exterior surface 24 applies a consistent pressureto the exterior surface 24 of the main pipe 12 to create a strongconnection between the distal end 22 of the branch pipe 10 and themating portion of the exterior surface 24 of the main pipe 12. To pushthe distal end 22 of the branch pipe 10 into the exterior surface 24 ofthe main pipe 12 with such consistent pressure, an opposed distal end 26of the branch pipe 10 is fitted with a cap 28 that has a vacuum 29operative to create a vacuum 108 within the branch pipe 10. Once thevacuum 29 is turned on, negative pressure is created within the cavity36 of the branch pipe 10. The negative pressure pushes the distal end 22of the branch pipe 10 into the exterior surface 24 of the main pipe 12.The branch pipe 10 is allowed to settle on the main pipe 12 so that theangle 14 may be different as intended if necessary. The settling insuresthat the pressure about the periphery of the distal end 22 on theexterior surface 24 of the main pipe 12 is consistent about the entireperiphery of the distal end 22.

Referring now to FIG. 2, a method of attaching the branch pipe 10 to themain pipe 12 is shown. The steps of the method shown in FIG. 2 will beexplained in conjunction with FIGS. 3-6. To attach the branch pipe 10 tothe main pipe 12, the distal end 22 of the branch pipe 10 may bepreformed or ground down to mate with the mating portion of the exteriorsurface 24 of the main pipe 12 are heated to their softeningtemperatures. These softening temperatures of the pipes 10, 12 varydepending on the material from which the pipes 10, 12 are fabricated. Byway of example and not limitation, common pipes 10, 12 are fabricatedfrom high density polyethylene (HDPE), low density polyethylene (LDPE),polyvinyl chloride (PVC), or polypropelene. For purposes of illustrationherein, pipes 10, 12 are fabricated from HDPE material. In this regard,the softening temperature for pipes 10, 12 which are fabricated fromHDPE material is about 440 degrees Fahrenheit to 500 degrees Fahrenheit.

As discussed above, the distal end 22 of the branch pipe 10 may bepreformed or ground down to mate with the exterior surface of the mainpipe 12. If the distal end 22 of the branch pipe 10 is preformed, thenthe distal end 22 of the branch pipe 10 may be formed with a lip thatprotrudes outward. The lip may protrude outward a small distance so thatthe pressure between the lip and the exterior surface of the main pipeis equal about the periphery of the distal end of the branch pipe. Whenthe distal end 22 of the branch pipe 10 is ground down to the shape ofthe exterior surface of the main pipe, then it is only the thickness ofthe branch pipe 10 that is fused to the exterior surface of the mainpipe. Moreover, when the distal end 22 of the branch pipe 10 is grounddown, then no special pipes are needed to make the connection. Standardstraight pipes are used and modified on site.

In heating the distal end 22 of the branch pipe 10 and the exteriorsurface 24 of the main pipe 12, the exterior surface 24 of the main pipe12 is melted 100. Moreover, the distal end 22 otherwise known as thesaddle end of the branch pipe 10 is melted 102. The distal end 22 of thebranch pipe 10 and the exterior surface 24 of the main pipe 12 aremelted with a plate 30. The plate 30 has a first side 32 having a convexconfiguration. The plate 30 also has a second side 34 having a concaveconfiguration. The concavity of the second side 34 of the plate 30approximates a curvature of the pipe 12 so that upon contact of thesecond side 34 of the plate 30, the heat emanating from the second side34 of the plate 30 can melt 100 the exterior surface 24 of the main pipe12. Similarly, the convex configuration of the first side 32 mirrors theconcavity of the second side 34 so that the first side 32 can melt 102the distal end 22 of the branch pipe 10. Prior to melting, the endportion of the branch pipe 10 may be cut or formed so that the shape ofthe distal end 22 closely approximates the shape of the exterior surface24 of the main pipe 12 to which the branch pipe 10 connects.

To hold the plate 30 against the exterior surface 24 of the main pipe 12and the distal end 22 of the branch pipe 10, a negative pressure 108 canbe created within the internal cavity of the branch pipe 10 with vacuum29. Additionally, such negative pressure may also be communicated tocavity 36 (see FIG. 8) through hole 44 of the plate. It is alsocontemplated that the through hole may be fitted with a fitting sizedand configured to receive a vacuum line. Initially, the vacuum line maybe connected to the fitting of the plate. The vacuum line providesnegative pressure between the plate and the main pipe to hold the heateron the main pipe while raising the temperature of the main pipe towardits softening temperature. This is accomplished without the branch pipeattached to the heater. After a period of time before the main pipereaches the softening temperature, the vacuum line is removed and thebranch pipe is attached to the heater/plate 30. A vacuum created in acavity of the branch pipe is communicated between the plate and the mainpipe through the fitting on the plate. The negative pressure within theinternal cavity of the branch pipe 10 and the cavity 36 between theplate 30 and the main pipe 12 continues to push the second side 34 ofthe plate 30 against exterior surface 24 of the main pipe 12 as well aspushes the distal end 22 of the branch pipe 10 against the first side 32of the plate 30. The heat from the plate 30 is communicated to theexterior surface 24 of the main pipe 12 and the distal end 22 of thebranch pipe 10. About ⅛ of an inch of the distal end 22 of the branchpipe 10 is raised to a softening temperature of the pipe 10.Additionally, a depth of about ⅛ of an inch of the exterior surface 24of the main pipe 12 is raised to the softening temperature of the pipe12. In this manner, when the distal end 22 of the branch pipe 10 and theexterior surface 24 of the main pipe 12 are directly attached to eachother, the respective materials can form a chemical bond therebetween.

When the exterior surface 24 of the main pipe 12 and the distal end 22of the branch pipe 10 is sufficiently heated as described above, thenegative pressure within the internal cavity of the branch pipe 10 andthe cavity 36 is removed so that the plate 30 can be removed 104 (seeFIGS. 2 and 4) from between the branch pipe 10 and the main pipe 12.Immediately thereafter, the distal end 22 of the branch pipe 10 isplaced in contact 106 (see FIGS. 2 and 5) with the exterior surface ofthe main pipe. The vacuum 29 is turned on again in order to create 108negative pressure within the internal cavity of the branch pipe 10. Asyou will note from FIG. 4, no through hole is formed in the exteriorsurface 24 of the main pipe 12 so that the negative pressure in theinternal cavity of the branch pipe 10 pushes the distal end 22 of thebranch pipe 10 into the exterior surface 24 of the main pipe 12. Theperiphery of the distal end 22 of the branch pipe 10 may not matchperfectly with the exterior surface 24 of the main pipe 12. In thisregard, as the negative pressure pushes the branch pipe 10 into the mainpipe 12, such mismatch may cause the branch pipe 10 to shift 110 fromits original intended angle. By way of example and not limitation, theoriginal intended skew angle 14 may be 45 degrees. However, due to themismatch between the concavity formed on the distal end 22 of the branchpipe 10 and the degree of the convex configuration of the exteriorsurface 24 of the main pipe 12, the skew angle 14 may be 45 degrees ±5degrees and more preferably ±2 degrees after connection of the branchpipe 10 to the main pipe 12. Such shifting equalizes the pressure aboutthe entire periphery of the distal end 22 so that the melted connectionbetween the distal end 22 and the exterior surface 24 of the main pipe12 has a consistent strength about the entire periphery of the distalend 22 of the branch pipe 10. As can be seen from FIG. 6, the distal end22 of the branch pipe 10 and the exterior surface 24 of the main pipe 12form a bead completely about the distal end 22 of the branch pipe 10.The connection is a liquid and airtight seal produced with even pressureabout the entire periphery of the distal end 22 against the exteriorsurface 24 of the main pipe 12.

Referring now to FIG. 3, the cap 28, as discussed above, may be in fluidcommunication with vacuum 29 so that the vacuum 29 can create a negativepressure within the internal cavity of the branch pipe 10. The cap 28 isshown as being disposed over an opposed distal end portion 38 to form anairtight seal therewith. The cap 28 may have a butterfly valve 40 and ableed valve 42. The butterfly valve 40 has an on position and an offposition. In the off position, when the vacuum 29 is activated, nonegative pressure is created within the internal cavity of the branchpipe 10. Also, there is no fluid communication between the vacuum 29 andthe internal cavity of the branch pipe 10. In the on position, as shownin FIG. 3, the vacuum 29, when the vacuum 29 is activated, negativepressure is created within the internal cavity of the branch pipe 10.Fluid communication is established between the vacuum 29 and theinternal cavity of the branch pipe 10. The butterfly valve 40 istraversed to the on position after holding the branch pipe 10 againstthe plate 30 and the plate 30 against the main pipe 12 in order to melt102 the distal end 22 of the branch pipe 10 and the exterior surface 24of the main pipe 12. The butterfly valve 40 may be traversed to the offposition to allow the heat to soak through the material. The butterflyvalve 40 is also traversed to the on position when the plate 30 isremoved from between the branch pipe 10, and the main pipe 12 and thedistal end 22 of the branch pipe 10 is placed in contact with and pushedagainst exterior surface 24 of the main pipe 12.

The bleed valve 42 remains closed when the vacuum 29 is activated andthe butterfly valve 40 is traversed to the on position. The bleed valve42 is opened in order to equalize the pressure in the internal cavity ofthe branch pipe 10 and the atmosphere. In this manner, the plate 30 canbe removed from between the branch pipe 10 and the main pipe 12. Moreparticularly, after the plate 30 has sufficiently melted 102 the distalend 22 of the branch pipe 10 and the exterior surface 24 of the mainpipe 12, the vacuum 29 may be deactivated and/or the butterfly valve 40may be traversed to the closed position. The bleed valve 42 may beopened so that air is introduced into the internal cavity of the branchpipe 10 to equalize the pressure within the internal cavity of thebranch pipe 10 to the atmosphere. Additionally, the pressure within thecavity 36 between the plate 30 and the main pipe 12 is also equalized tothe atmospheric pressure. Now the branch pipe 10 may be removed from theplate 30 and the plate 30 may be removed from the main pipe 12. Thebleed valve 42 may be placed downstream of the butterfly valve 40 and bedisposed between the cap 28 and the butterfly valve 40.

The vacuum 29 and the cap 28 may be in fluid communication with eachother by flex line 44. The flex line 44 does not collapse in thepresence of negative pressure. The cap 28 is shown as being attachedover the opposed distal end portion 38 of the branch pipe 10. However,other configurations of the cap 28 are also possible. By way of exampleand not limitation, the cap 28 may be a flange that mates with theopposed distal end of the opposed distal end portion 38 of the branchpipe 10 and a protrusion that is sized and configured to an innerperiphery of the branch pipe 10. The cap 28 regardless of whether thecap 28 is placed over the opposed distal end portion 38 of the branchpipe 10 or placed within may be fabricated from a generally flexiblematerial and be somewhat conformable so that the cap 28 may conform tothe opposed distal end portion 38 of the branch pipe 10 to form a fluidtight seal between the cap 28 and the branch pipe 10.

Referring now the FIGS. 4, 7 and 8, the plate 30 defines the first side32 and the second side 34. The first and second sides 32, 34 of theplate 30 preferably match the configuration of the exterior surface 24of the main pipe 12. Although the apparatus and method described hereinrelates to the joining of a distal end 22 of the branch pipe 10 to around or circular main pipe 12, the apparatus and method describedherein may be used to join a branch pipe 10 to a main pipe 12 havingother configurations such as oval, rectangular, square, etc. Theapparatus and method described herein is beneficial in joining thebranch pipe 10 to the main pipe 12 at a skewed angle 14 since it isdifficult to push the branch pipe 10 into the main pipe 12 by hand whenthe angle is skewed. The vacuum 29 creates negative pressure to hold thebranch pipe 10, plate 30 and the main pipe 12 together during melting aswell as the branch pipe 10 and the main pipe 12 together during joining.It is also contemplated that the branch pipe 10 may also be attached tothe main pipe 12 at a right angle.

As discussed above, the second surface 34 of the plate 30 is concave.The concavity of the second surface 34 is supposed to match theroundness of the second pipe 12. Unfortunately, the pipe 12 maysometimes not be truly round thereby causing an imperfect match betweenthe second side 34 of the plate 30 and the exterior surface 24 of thesecond pipe 12. As shown in FIG. 9A, in this example, the outerboundaries have a greater gap 54 compared to the inner boundaries asreferenced by gap 56, or vice versa. Due to the variance, it may take asignificantly longer period of time in order to establish a seal betweenthe second side 34 of the plate 30 and the exterior surface 24 of thesecond pipe 12. Accordingly, the second side 34 may be retrofitted witha cup 59 having a small diameter 58. The small diameter cup 59 due toits smaller diameter or size more quickly forms the seal with theexterior surface 24 of the second pipe 12. The cup 59 may be heated andcapable of penetrating the exterior surface 24 of the second pipe 12faster. As such, the user may initially push the cup 59 into theexterior surface 24 of the second pipe 12 for a short period of timebefore a seal between the cup 59 and exterior surface 24 is formed. Oncethe seal is formed, negative pressure is communicated through thethrough hole 44 into the cavity 36 to continue pushing the second side34 of the plate 30 toward the exterior surface 24 of the second pipe 12.The through hole 44 may be fitted with a fitting that can receive avacuum line. Also, the seal with the main pipe can be establishedthrough other means other than a cup in the plate. For example, a gasketmay be disposed between the plate and the exterior surface of the mainpipe or a cup may be formed in the exterior surface of the main pipe.

Referring now to FIG. 10, after the distal end 22 of the first pipe 10is attached to the exterior surface 24 of the second pipe 12, a drillbit48 may be inserted into the cavity of the first pipe 10. The drillbit 48is rotated with the drill 50 and used to generate a hole through theexterior surface 24 of the second pipe 12. The hole 52 provides fluidcommunication between the first and second pipes 10, 12. Moreover, theouter diameter of the drillbit 48 closely approximates the innerdiameter of the first pipe 10. After the hole 52 is formed by thedrillbit 48, the interior surfaces of the joint between the first andsecond pipes 10, 12 are filed or sanded down so that no sharp edgesexist therebetween pipes 10, 12 so that the fluid and solid materialsflowing through the first pipe 10 into the second pipe 12 are nothindered.

Furthermore, as shown in FIG. 11, it is also contemplated that theapparatus and method may be used to join a distal end 22 of a first pipe10 to a distal end 19 of a second pipe. In this regard, the first andsecond sides 32, 34 of the plate 30 may be flat. The opposed distal end22 of the second pipe may be sealed off to provide for a liquid tightenvironment within the cavity of the second pipe 12. When the plate 30is disposed between the distal ends 19, 22 of the first and second pipes10, 12 and the cap 28 is placed on the opposed distal end portion of thefirst pipe 10 with the vacuum 29 activated, negative pressure is createdwithin the cavity of the first pipe 10 and such negative pressure isalso communicated to the cavity of the second pipe 12 to push the firstand second pipes together on the plate 30.

The plate 30 has a through hole 44 which communicates the negativepressure from one side of the plate 30 to the other side of the plate30. In particular, the negative pressure created within the cavity ofthe branch pipe 10 is communicated to the cavity 36 (see FIG. 8) on thesecond side of the plate 30. Additionally, the negative pressure createdwithin the first pipe is created within the internal cavity of thesecond pipe via the through hole 44.

The first and second sides 32, 34 may have a texture formed thereon. Assuch, when the first and second sides 32, 34 of the plate 30 are placedon the distal end 22 of the branch pipe and the exterior surface 24 ofthe main pipe 12, no negative pressure is created within the internalcavity of the branch pipe 10 or the cavity 36 between the plate 30 andthe main pipe 12. The textured form allows for the transfer of air thatprevents the formation of a liquid tight seal. Instead, the user mayneed to initially push the branch pipe 10 against the plate 30 and themain pipe 12 by hand until the heat from the first and second sides 32,34 of the plate 30 melts the distal end 22 of the branch pipe 10 and theexterior surface 24 of the main pipe 12 to form a liquid tight sealtherebetween.

The plate 30 may also be attached to a handle 46 to aid in removing theplate 30 from between the branch pipe 10 and the main pipe 12. Thehandle 46 is insulated so that the user can grip the handle 46 with alight glove or a bare hand.

Referring now to FIG. 12, a second embodiment of a method and apparatusfor joining first and second pipes 10, 12 is disclosed. The apparatusmay include a sleeve 60 that is sized and configured to wrap around boththe internal surface 62 and the exterior surface 24 of the pipe 10, 12.The sleeve 60 may be connected to a cooling unit 64 which actively coolsdown the sleeve 60. Cold water may flow through the sleeve 60.Alternatively, the sleeve may be a thermoelectric cooler. When thesleeve 60 is placed over the distal end portion 66 of the pipes 10, 12,the sleeve 60 is operative to reduce the temperature of the distal endportion 66. By reducing the temperature of the distal end portion 66 ofthe pipe 10, 12, heat introduced into the distal end 68 of the pipe 10,12 can be more quickly removed therefrom to lower the temperature belowits softening temperature so that the operator need not wait as long forthe heated portions of the pipes 10, 12 to cool to form the joint 20.

When the plate 30 heats up the distal end 68 of the pipes 10, 12 inorder to raise its temperature above the softening temperature of thepipes 10, 12, the heat penetrates the distal end 68 of the pipes 10, 12a distance 70 that is less than the distal end portion 66. As such, asmaller portion 70 is raised to the softening temperature of thematerial of the pipes 10, 12. During operation, the sleeve 60 cools downthe entire distal end portion 66 of the pipes 10, 12. In contrast, theplate 30 raises the temperature of the distal ends 68 of the pipes 10,12 above the softening temperature of the material of the pipes 10, 12.In other words, the portions 70 of the pipes 10, 12 are raised to thesoftening temperature.

In other words, the portions 70 of the pipes 10, 12 are raised to thesoftening temperature while the remaining portion 72 remains at atemperature lower than the softening temperature. After the plate 30 isremoved and the distal ends 68 of the pipes 10, 12 are pushed together,the heat from the portions 70 is drawn into the remaining portion 72 toaccelerate cool down of the smaller portions 70 of the pipes 10, 12. Inorder to assist in the process, the various aspects and method stepsdescribed in relation to the vacuum 29 and the cap 28 may be used injoining the distal ends 68 of the first and second pipes 10, 12.

The above description is given by way of example, and not limitation.Given the above disclosure, one skilled in the art could devisevariations that are within the scope and spirit of the inventiondisclosed herein, including various ways of forming the cap. Further,the various features of the embodiments disclosed herein can be usedalone, or in varying combinations with each other and are not intendedto be limited to the specific combination described herein. Thus, thescope of the claims is not to be limited by the illustrated embodiments.

1. A method of forming a liquid tight seal between a distal end of afirst pipe and a second pipe, the first and second pipes fabricated frompolyethylene, polyvinyl chloride or polypropylene material which definesa selected material, the method comprising the steps of: heating thedistal end of the first pipe with a heater, the distal end of the firstpipe defining an inner peripheral edge and an outer peripheral edge, theheater being applied to the distal end of the first pipe until an entiresurface of the distal end between the inner peripheral edge and theouter peripheral edge of the first pipe have reached a softeningtemperature of the selected material; heating the second pipe, after theheating steps, removing the heater from the first pipe; after theheating steps and the removing step, directly contacting the distal endof the first pipe to the second pipe; creating a negative pressurewithin a cavity of the first pipe after the contacting step so that thedistal end of the first pipe is pushed into the second pipe; applyingeven pressure about the circumference of the distal end of the firstpipe into the second pipe.
 2. The method of claim 1 wherein the heatingstep is performed until at least ½ inch of the distal end of the firstpipe has reached the softening temperature.
 3. The method of claim 1wherein heating step is performed with a plate having opposed first andsecond sides sized and configured to mate with the distal end of thefirst pipe and the exterior surface of the second pipe.
 4. The method ofclaim 3 wherein the first side has a convex configuration and the secondside has a concave configuration.
 5. The method of claim 4 wherein thesecond side of the date of the heater has an outer peripheral edgelarger than the outer peripheral edge of the distal end of the firstpipe and an annular protrusion smaller than the inner peripheral edge ofthe distal end of the first pipe, and the method further comprises thesteps of: forming an annular indentation into the exterior surface ofthe second pipe with the heated, annular protrusion of the plate;creating negative pressure within a space defined by the annularprotrusion of the plate of the heater, the plate of the heater and theexterior surface of the second pipe.
 6. The method of claim 3 whereinthe first side is flat and the second side is flat.
 7. The method ofclaim 1 wherein the creating the vacuum step includes the step ofcapping an opposed distal end of the first pipe with a cap which is influid communication with a vacuum device for creating the negativepressure.
 8. The method of claim 1 wherein the applying, step includesthe steps of allowing an angular relationship between the first pipe andthe second pipe to change as negative pressure is applied to the cavityof the first pipe and the distal end of the first pipe is pushed intothe second pipe.
 9. The method of claim 1 further comprising the step ofcreating the negative pressure within the cavity of the first pipeduring the heating step so that the negative pressure created in thecavity of the first pipe is sufficient to hold the first side of theplate of the heater on the distal end of the first pipe.
 10. The methodof claim 9 wherein the plate of the heater has a through hole so thatthe negative pressure created in the cavity of the first pipe is appliedbetween the plate and the second pipe to hold the plate on the secondpipe.
 11. The method of claim 1 wherein the distal end of the first pipeis attached to an exterior surface of the second pipe.
 12. The method ofclaim 1 wherien the distal end of the first pipe is attached to a distalend of the second pipe, and the vacuum is created by capping an opposeddistal end of the second pipe. 13-20. (canceled)
 21. The method of claim10 wherein the channel is a through hole.
 22. The method of claim 1wherein the step of heating the second pipe comprises the step ofcontacting an exterior surface of the second pipe to a protrusion of theheater.
 23. The method of claim 22 wherein the protrusion has a cupconfiguration and the exterior surface of the second pipe is placed intocontact with the cup.